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Freakiest things in our solar system

  1. Dec 21, 2007 #1
    Just a light-hearted post.

    What are in your opinion, the freakiest things in our solar system. Here are my votes.

    1) The axis of rotation of Uranus.

    2) The two moons (Saturn I think) that leap frog each other instead of colliding.

    3) The football shaped minor planet 2003 EL61

    Any more?
  2. jcsd
  3. Dec 22, 2007 #2


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    1) Neptune's moon, Triton

    2) Evo
  4. Dec 22, 2007 #3
    1) Uranus' moon Miranda - the one that looks like it was smashed to pieces and put back together by a schizophrenic Dutch painter

    2) The coloration of Saturn's moon Iapetus.

    3) Courtney Love
  5. Dec 22, 2007 #4
    Life on Earth
  6. Dec 22, 2007 #5


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    Pixel's right; life. I mean, what the heck is up with that?! Some kind of trick to reverse the flow of entropy? Making the energy streams run backward; we are an entropic irrigation system!

    (Though I may not be for much longer :bugeye:)
  7. Dec 22, 2007 #6


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    Why do you say it does that?

    2004 XR190, aka Buffy.

    And of course, Chirstopher Walken.
    Last edited: Dec 22, 2007
  8. Dec 23, 2007 #7


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    Does this mean I'm going to live?!:confused:

    Just showing my age. In the old days, this was the definition of "life" given in elementary schools. "Life is the ability to reverse entropy, however innefficiently or temporarily." It goes to the heart of all those questions you get asked when you first start to study biology, like "if fire eats, breathes, grows, and reproduces, why isn't it life?" and "why does a dead twig lying in the sun get hot, while the grass on which it lies remains cool?" Life is said to reverse entropy in the sense that, rather than breaking down into simpler and simpler forms, giving off energy as they go, living things take in energy and build up into more and more complex forms.

    A lot of folks today don't like that dfinition, but I still do.
  9. Dec 23, 2007 #8
    life increases entropy I think, we for example break down complex "food" into heat and simple substances like amino acids, I think the definition refers to the fact that the creation of life in the first place is a huge localized decrease in entropy which is highly improbable.
  10. Dec 23, 2007 #9
    Theres a fair few things in our solar system that i can never get my head around.

    1) The coronal heating problem, and solar wind acceloration above the photosphere.

    2) Origin of the asteriod belt.

    3) Origin of our moon.

    4) Why the Earths core is able to stay so hot.

    5) Jupiters moon Europa, and whatever lies beneath its frozen surface.

    6) Comet holmes

    At the moment, i would say that comet holmes is by far the biggest enigma in the solar system. I dont think many astronomers were predicting that its coma would outgrow the diameter of the sun! quite an enigma if there ever was one.
  11. Dec 23, 2007 #10


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    I thought you were previously refering to a lowering of the total entropy of the universe (i.e., a violation of the second law), rather than a local reduction.

    What about gravitational collapse (formation of stars and planets) in an open system, crystal growth (snowflakes et al), etc.? Aren't these all examples of local entropy reduction?
    Last edited: Dec 24, 2007
  12. Dec 31, 2007 #11
    The freakiest thing I'd say that hasn't been mentioned yet is the fact that the moon and sun are exactly the same size in the sky.
  13. Dec 31, 2007 #12
    Obviously that's explained by their different distances from Earth. I'm sure you already knew that because it's pretty obvious, but I guess it is still interesting if they are truly exactly the same size from our perspective. I never bothered to actually compare them.

    I think the fact that Earth happens to have the perfect conditions to harbor intelligent life is pretty impressive. Also that it's managed to avoid a catastrophic asteroid impact for thousands or millions of years while our neighbor Mars may now be due for a big one.
  14. Jan 6, 2008 #13

    the asteroid belt was thought to be created by a planet being obliterated by a huge collision, I think we have simulations that show that a certain type of glancing collision (and then a second one upon return) would cause the formation of one moon about the size of ours, the core being hot is just radioactive decay right? (if anything the earth's magnetic field is a bigger mystery), whats so bad about these explanations?
  15. Jan 6, 2008 #14


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    The asteroid belt is not thought to have been created by a planet being obliterated by a huge collision.

    There are some asteroid families, which have similar orbital elements, that are thought to have been the debris left after a larger asteroid suffered a collision, but as a whole the asteroid belt consists of planetesimals left over after the main planetary formation process had finished.

    The asteroid belt remains because each individual asteroid inhabits a safe stable orbital element parameter space 'shepherded' by the gravitational field of Jupiter.

  16. Jan 8, 2008 #15

    The freakiest thing is how come we only spotted this asteroid at the end of November 2007, if it was on a collision course with Earth, that wouldn't give us much time to do anything about it.
  17. Jan 8, 2008 #16


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    We're getting better at it! It isn't uncommon for us to detect asteroids like that after they have passed the Earth!
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